Eh...I'd personally avoid coffee grinders, since they tend to pulverize anything and everything in their path.

Per a previous post on milling that I read, just take a standard rolling pin, 2 sheets of wax paper (1 on top, 1 on bottom), and gently crush until you get a decent consistency of crushed grain vs. hulls. Too many crushed hulls would result in heavier tannins in the final brew.

well... its probably not great, but for partial mashes since I'm still brewing with plain dried extract I will just use my small starbucks blade grinder and pulse my grains. Takes about 1-2 minutes to get 2-3 pounds of grain into my very-fine straining bag. I'd say 1/4 is pulverized, 1/2 is cracked just right, and 1/4 is barely cracked or intact. Anyway since its a partial i'm really going for increased and robust flavor not so much high effeciency fermentables. I've been really pleased with the results. I don't find much if any tannin flavor leeches out during the partial mash and its been very handy for me personally. The key is the very-fine straining bag so almost no particulate matter enters the wort during boiling afterwards.

It's certainly not optimal, but I live in a small apartment and I can't have more beer equipment like a grinder right now. I will just make do for now. Someday i'll have lots of room and a man area that won't disturb the significant other as much as it already does.

Coffee grinders are designed to do very small batches......1-2 oz. of beans at a crack, tops. The directions that came with our very nice quality burr coffee mill (Baratza Maestro) specifically enjoin against grinding continuously for more than a few minutes without allowing the machine too cool off a while. My conclusion would be that milling grain in a coffee mill -even a pound of specialty grains- is just asking to burn out a perfectly good coffee mill for no good reason.

I mill all my grain in a very inexpensive Corona-type mill, bought off eBay for less than $25 delivered. To take out the hand labor, I just adapted an electric drill to it with a $ 0.25 hardware store bolt.

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“Malt does more than Milton can / To justify God’s ways to man”

I always have small amounts of specialty grains that I can't get at my LHBS at home that I order from NB or William' Brewing. I use a mortar and pestle to crush them. I end up with a variety of sizes of crushed grains, but most importantly the hulls are still intact. It's not ideal, but it works for a quarter or a half pound here and there. Plus, I already have it.

Coffee grinder just turns whole grain to cut up grain, including the hulls.